This is the perfect place for your question and I've got an answer for you.
The only way you can tell whether you're losing
fat or
water or
muscle (a bad thing to lose!) is by checking your body fat percentage. Finding out your body fat % (also written as BF%) tells you what your body composition is - how much of your weight is fat pounds and how much of it is pounds of lean body mass (LBM). You know what fat is, of course -
- and LBM is simply everything in your body that
isn't fat, like bone, skin, hair, water, and muscle.
Our goal when we're losing weight is to make it as close to 100% fat lost as possible. It's never going to be 100% fat, but we want to minimize the loss of LBM to the greatest extent possible. Muscle is precious because it burns calories and keeps your metabolism high, so you really don't want to be losing muscle instead of fat.
How can you find out what your BF% is? The easiest way is if you belong to a gym. A trainer can check it with calipers or a bioelectrical impedance device (like an Omron hand-held body fat calculator). Calipers, especially a nine-site test done by someone with experience, are fairly accurate.
Outside of a gym, a dunk tank or BodPod is very accurate, but they're in limited locations and cost $$. Instead, you can buy home scales that calculate body fat % (like some of the Tanitas) - they use bioelectrical impedance and, like the Omron, aren't super accurate but ARE useful for tracking trends over time. Least accurate, IMO, but very easy to use is an on-line calculator that uses your body measurements, like waist and hips.
Once you find out what your BF% is, you'll be able to tell what % of your body weight is fat and what is LBM. From that point on, you'll re-check your BF (using the same technique) at regular intervals, like once a month. That's how you'll be able to tell the composition of the weight you're losing - whether it's LBM or fat.
Let's say you start at 200 pounds and your BF% is 35%. You multiply your weight by your BF% (200 X .35) and find out that you have 70 pounds of fat on your body.
Then a month later you check again. You've lost ten pounds, let's say, and your BF% calculates out to be 33%. So you multiply your weight by your BF% again (190 X .33) and you find out that you now have 62 pounds of fat on your body. You know that you lost ten pounds and that eight of them were fat pounds and two were pounds of LBM.
And you keep tracking just like that each month or however often you want to check.
What you
can't tell is what kind of LBM you've lost - whether it's muscle or water. So we just focus on losing fat pounds.
I hope this wasn't too confusing!
Weight question
